Motors and Generators
Motors and Generators
•
•
•
•
•
Electromagnets
Magnet Poles
Parts of a Basic DC Motor
Electric Generators
From the Power Plant to Your Home
Motors and Generators
Small DC Motor
Image courtesy of DOE / NREL
Geothermal Generator
Generator in a
Hydro Plant
Electric Turbine
Generator
Electromagnets
N
S
Electromagnet ends
change between north
and south depending
on the direction of the
current.
S
N
Magnet Poles
Remember that opposite poles attract and like
poles repel.
If you alternate the middle magnet’s poles, it will
continue to spin.
N
N
S
S
This is how motors can turn!
Parts of a Basic DC Motor
Motor: A device used to convert electric energy into
mechanical energy.
Brush
DC Source
Commutator
N
N
Permanent
Magnet
Armature
S
Permanent
Magnet
S
Commutator
Brush
Parts of a Small DC Motor
Brushes
Wire
Connections
Permanent
Magnets
Armature
Commutator
Electric Generators
Generator: A device used to convert mechanical
energy into electrical energy.
Mechanical motion turns the armature which creates current.
Many DC motors can function as a generator.
N
N
S
S
From the Power Plant to Your Home
Image courtesy of Sacramento Municipal Utility District
Power plants
generate electricity.
From the Power Plant to Your Home
Step up transformers increase voltage for
transmission across large towers.
Increased voltage increases efficiency.
From the Power Plant to Your Home
Images courtesy of DOE / NREL
Large towers transmit electricity over long
distances.
From the Power Plant to Your Home
Step down transformers reduce voltage
at substations to acceptable levels for the
end user.
From the Power Plant to Your Home
Electricity arrives at your home at a
junction box.
Usage is measured with a meter.
Preparing Your Armature
Step One: Wrap the Coil
1)
Cut a 3ft section of Magnet wire
2)
Start coiling the wire 3” from the end of end of
the wire. Wrap the wire around a 1”diameter
dowel rod until a 3” length remains.
3)
Carefully hold the coil together and pull it off of
the dowel rod. Wrap the coil with the 3” lengths
you had left at the beginning and end of your
coil.
Step Two: Sand the Contacts
Coil
Contact
1) Sand the top half
of the contact on one
side
Contact
2) Sand all the way
around the contact on the
other side
Motors and Generators
•
•
•
•
•
Electromagnets
Magnet Poles
Parts of a Basic DC Motor
Electric Generators
From the Power Plant to Your Home
Image Resources
Microsoft, Inc. (2008). Clip Art. Retrieved September 10, 2008, from
http://office.microsoft.com/en-us/clipart/default.aspx
National Renewable Energy Laboratory (2008). Photographic
information eXchange. Retrieved November 5, 2008, from
http://www.nrel.gov/data/pix/searchpix.html
Sacramento Municipal Utility District (SMUD). (2008). Power plant
[Image]. Sacramento: Sacramento Municipal Utility District.